Ladle addition feeding mechanism with independently controlled feeder conveyor



Dec. 7, 1965 J. H. REIGHART 3,221,380

LADLE ADDITION FEEDING MECHANISM WITH INDEPENDENTLY CONTROLLED FEEDERCONVEYOR 3 Sheets-Sheet 1 Filed Dec. 21, 1962 INVENTOR. hfRe'w'ha/rfi w,wadflnw W Ju/ne ATTORNEYS Dec. 7. 1965 J. H. REIGHART 3,221,380

IJADLE ADDITION FEEDING MECHANISM WITH INDEPENDENTLY CONTROLLED FEEDERCONVEYOR Filed Dec. 21, 1962 5 sheets-sheet 2 97 I NVENTOR.

June hffielylwyrfi Wu, WW4? M ATTORNEYS Dec. 7, 1965 J RE|GHART3,221,380

LADLE ADDITION FEEDING MECHANISM WITH INDEPENDENTLY CONTROLLED FEEDERCONVEYOR Filed Dec. 21, 1962 3 Sheets-Sheet 5 START IO 10 10 K) STOP 1[:2 LMIERJO HOPPER 78/ \77 W LOAD CELLS 68 (3 OR 4) 75 69 82 INDIC 83 80ra u u 8 DIAL JO CONTROL |NSTRUMENT\ 86 as as ELEC MOTOR 3-? 1' 76 Z/ lL INVENTOR.

62 63 64 65 JZLHEHRGZZYILHIZ BY 59- $MW, MW8 W ATTORNEYS United StatesFatent O 3,221,380 LADLE ADDITION FEEDING MECHANISM WITH INDEPENDENTLYCONTROLLED FEEDER CON- VEYOR June H. Reighart, 1991 Lee Road, Cleveland18, Ohio Filed Dec. 21, 1962, Ser. No. 246,498 Claims. (CI. 22-82) Be itknown that, I, June H. Reighart, a citizen of the United States,residing at Cleveland, Cuyahoga County, Ohio, have invented certainimprovements in Ladle Addition Feeding Mechanism, of which the followingis a specification.

The invention relates to means for feeding additions of alloyingmaterials and the like to the molten metal in a ladle while an openhearth, electric furnace, or other steel making furance is being tapped.

The invention relates more particularly to means for feedingpredetermined amounts of different alloying materials to the ladle. Itis known that apparatus has been devised including electricload-measuring means supporting a hopper from which a predeterminedamount of material may be fed.

Such devices are adapted to feed the material immediately into a ladle,or the like, as it is discharged from the supply hopper. Such devicesmust be operated immediately up tapping of the furnace. As these devicesinclude load-measuring means, a failure of electric power at the timethe furnace is tapped would render the automatic feeding device useless.

It is a principal object of the present invention to provide a ladleaddition feeding apparatus including electric load-measuring means forfeeding pre-measured amounts of alloying materials upon a normallystationary, substantially horizontal, feeder conveyor which may be inthe form of a shaker pan, prior to the tapping of the furnace, or ifdesired, simultaneously with the tapping of the furnace, with means forreciprocating the shaked pan during the tapping of the furnace forcontinuously feeding the material from the shaker pan to the ladle.

Another object of the invention is to provide both electric andfluid-operated means for selective operation of the vibrating mechanismfor the shaker pan.

A further object of the invention is to provide mechanism of thecharacter referred to in which the gate controlling discharge ofmaterial from the hopper may be selectively operated by electric orfluid drive means.

A still further object of the invention is to provide a pivoted chute atthe discharge end of the shaker pan with means for automaticallyswinging the chute upon its pivot to direct the material toward thecenter of the ladle as the ladle is moved toward the furnace during thetapping operation.

Another object of the invention is to provide mechanism of thischaracter in which the ladle is moved on a car, and a mast upon theladle car contacts a pivot bar on the pivoted chute to swing the chuteupon its pivot as the ladle car is moved.

A further object of the invention is to provide apparatus of thecharacter referred to in which hinged heat shields are provided for theelectric load-measuring cells which support the hoppers.

It is also an object of the invention to provide such a heat shieldcomprising spaced walls of metal with a layer of heat insulationmaterial therebetween.

A still further object of the invention is to provide a device of thecharacter referred to in which the gate for the hopper is in the form ofa rotary bucket.

Another object of the invention is to provide a feeding apparatus havinga conveyor or shaker pan with side extensions to form a container withcapacity for the maxice imum requirement for ladle additions for onefurnace heat.

A further object of the invention is to provide mechanism of thecharacter referred to in which all controls including the scale dials,indicator lights, gate operating controls, selector switch, conveyoroperation controls, including rate of feed and alternate drive means,and bypass manual control means for weighing and conveying may be housedin a single cabinet located in a control station.

A still further object of the invention is to provide such a device inwhich the pivoted chute is provided with mechanical means such as acounter-balance device for retracting the chute when not in use.

Another object of the invention is to provide apparatus of the characterreferred to in which a lip or ledge is provided at the discharge end ofthe hopper gate to reduce dribble of material after the operation of thegate has been discontinued.

The above and other objects, apparent from the drawings and followingdescription, may be attained, the above described difficulties overcomeand the advantages and results obtained, by the apparatus, construction,arrangements and combinations, sub-combinations and parts which comprisethe present invention, a preferred embodiment of which, illustrative ofthe best mode in which applicant has contemplated applying theprinciple, being set forth in detail in the following description andillustrated in the accompanying drawings; in which FIG. 1 is a sideelevation of one embodiment of the invention;

FIG. 2 is a front end elevation of the apparatus shown in FIG. 1;

FIG. 3 is a top plan view of the apparatus shown in FIGS. 1 and 2;

FIG. 4 is an enlarged fragmentary side elevation of a portion of theframe and feeder conveyor showing the longitudinal and lateral guiderollers for the reciprocating shaker pan of the conveyor;

FIG. 5 is a fragmentary transverse section taken on the line 55, FIG. 4;

FIG. 6 is an enlarged side elevation of one of the load cells with heatshield therefor as used intermediate the corners of a hopper, showingthe hinged portion of the heat shield in open position;

FIG. 7 is a further enlarged transverse, horizontal sec tion, taken ason the line 7-7, FIG. 6, with the hinged portion of the heat shieldclosed;

FIG. 8 is an enlarged transverse horizontal setcion of a heat and impactshield as used for the load cells at corners of a hopper;

FIG. 9 is a schematic wiring diagram for one of the hopper gates asshown in FIGS. 1 to 3; and,

FIG. 10 is an enlarged fragmentary elevation of a rotary bucket-type ofgate for the hoppers.

Referring first to the embodiment of the invention shown in FIGS. 1 to3, a pair of storage hoppers are indicated at 1 and 2 for containing asupply of alloying material. The most commonly used alloys for ladleadditions are ferro-manganese and ferro-silicon and each hopper maycontain a supply of one of these materials.

Both hoppers are of the same construction, each having the downwardlytapered lower portion 3 with outlet 4 at its lower end. These hoppersare assembled in a frame, indicated generally at 5, which may be mountedupon a lower support 6, as indicated in the drawings, or suspended fromsuitable hangers or the like attached overhead.

Any suitable gate means may be provided for controlling the outlet foreach hopper. For purpose of illustration only, the gate is shown in thisembodiment of the in- 3 vention as a pan 7 located beneath the outlet 4of each hopper and adapted to be vibrated longitudinally. In order toreduce dribble of material from either hopper after operation of thegates has stopped, a lip or ledge 7a is formed at the discharge end ofeach gate.

For the purpose of illustration, each of these gates is shown as adaptedto be selectively vibrated by an electric vibrator indicated at 8 or anair vibrator indicated at 9. These vibrators may be of the type sold byMartin Engineering Company under the trademark Vibrolator, for which itis understood patents are pending.

Each hopper is supported upon the frame by electric load cells,indicated generally at 10, which are electrically connected to weightindicating and recording scale dials indicated generally at 11 in themanner to be later described. Both the load cells and weight indicatingand recording scale dials may be of a type sold by The Atlas Car andManufacturing Company, which are disclosed in patents owned by saidcompany, and for which it is understood other patents are pending.

Located beneath the hopper, within the frame 5, is a longitudinallydisposed feeding conveyor 12 having stationary side Walls 13 and rearend wall 14, and its bottom formed by a longitudinally disposedreciprocating shaker pan 15 which is operated independently of the gates7 for the hoppers 1 and 2.

This feeder conveyor has a capacity for the maximum requirement ofmaterials for additions for one heat of a furnace. Thus, if desired,while the shaker pan 15 remains stationary, the gates of the hoppers 1and 2 may be operated to discharge the desired amount of alloyingmaterials from these two hoppers to the conveyor 12.

In addition to this, any desired pro-weighed amount of any otheralloying material or materials may be placed in the conveyor 12,together with such customary materials as packages of aluminum, bags ofcarbon and the like.

Means is provided for operating the shaker pan 15 of the conveyor 12independently of the gates of the hoppers 1 and 2 so that after thecomplete requirement for one heats additions have been charged into thefeeder conveyor, the shaker pan 15 thereof may be longitudinallyreciprocated to discharge the materials therefrom into the ladle.

With such an arrangement, the hopper gates may be operated prior to thetapping of the furnace so that in the event any trouble develops in themechanism for discharging the pre-measured material from the hoppers,there may be sufficient time to correct the trouble before the furnaceis tapped.

Thus, the conveyor 12, positioned beneath the hopper gates, may receivethe metered material from the hoppers and hold it until the furnace istapped, and then feed the additions into the ladle, together with theother hand and miscellaneous, pre-weighed additions which may have beenalso placed on the conveyor.

It should be understood, however, that the shaker pan 15 of the conveyormay, if desired, be operated to feed addition materials into the ladleat the same time that the material is being metered out from thehoppers. Since each hopper and the feeder conveyor may be independentlycontrolled, the timing is at the option of the operator.

The shaker pan 15 of the feeder conveyor is adapted to be reciprocatedby a vibratory drive unit indicated at 16 (FIG. 1) connected to the rearend of the shaker pan as indicated at 17. This drive unit 16 is adaptedto reciprocate the shaker pan 15 longitudinally, the forward movementbeing relatively slow, as compared with the rearward movement, so as tocontinuously discharge material from the forward end of the pan at acontrolled rate.

The vibratory drive unit 16 is arranged to be selec tively operated byan electric motor 18 or an air motor 19, either of which may be theprimary drive means for 1 the unit 16 and the other the auxiliary drivefor use in the event of failure of the primary drive.

The conveyor drive unit 16 is connected to the drive motors 18 and 19,as by chain and sprocket gearing 20 with override type clutches, asindicated at 21, so that either drive motor may be used while the otherstands still, with no switch-over operation involved.

It will be understood that this conveyor drive means operates entirelyindependently of the weighing controls for metering predeterminedamounts of material from the hoppers 1 and 2.

Conventional electric circuit means is connected to the electric motor18, with control switch in the circuit at a remote point, such as acontrol panel. The air motor 19 is in like manner connected to aconventional pneumatic line, with control valve therefor on the controlpanel.

Referring to FIGS. 4 and 5, the lower edges of the stationary side wallsof the conveyor are attached to and supported upon the inturned fianges22 on the channelshaped conveyor frame member 23.

Upturned longitudinal flanges 24 are formed at the edges of the shakerpan 15, and extend upwardly, spaced outwardly from the depending edgesof the stationary side walls 13 of the feeder conveyor.

For the purpose of mounting the shaker pan 15 for longitudinal movementrelative to the stationary side walls 13, an angle member 25 is weldedor otherwise attached within each side of the channel-shaped conveyorframe member 23.

As best shown in FIG. 5, the upper edge of the vertical flange of theangle member 25 is attached to the underside of the adjacent inturnedflange 22, and the outer edge of the horizontal flange 26 of the anglemember is attached to the inner surface of the adjacent vertical sideWall 27 of the channel frame member 23.

Spaced blocks 28 with elongated cut-outs 29 in their upper sides arewelded or otherwise attached to the under surfaces of the horizontalflanges 26 of the angle members 25 and depend therefrom.

Transversely disposed, inverted channel members 30 are attached atcorrespondingly spaced points to the lower surface of the shaker pan 15.A plate 31 is welded within each end of each channel member 30, and aspindle 32 is located through a suitable opening in said plate andsecured thereto as by a nut 33.

A roller 34 is journalled on the spindle 32 and located within thecut-out 29 of the corresponding block 28. This limits the longitudinalmovement of the shaker pan.

For the purpose of preventing lateral play of the shaker pan, atransversely disposed channel member 35 has opposite ends attached tothe under surfaces of the horizontal flanges 26 of the angle members 25at each side of the stationary channel frame member 23 of the feederconveyor.

An angle bracket 36 is connected to the closed lower surface of thechannel member 35, at the center thereof, and an inverted channelportion 37 thereof is disposed beyond one side of the channel member 35.

A vertical spindle 38 is secured to the channel portion 37 of thebracket 36, by the nut 39, and a roller 40 is journalled upon the upperportion of said spindle. The roller 40 is received between the guideflanges 41 of the bracket 42, which is attached to and depends from theunderside of the shaker pan 15, at the longitudinal center thereof.

As best shown in FIG. 5, the shaker pan 15 is preferably provided withlongitudinal corrugations or ribs 43, which reinforce the pan and assistin keeping the materials distributed transversely thereon.

The pan 15 of the feeder conveyor discharges onto a gravity chute 43which directs the ladle additions into the ladle at the desired pointfor maximum alloying results. This chute may be positioned stationaryrelative to the frame 5, or may be arranged to be rotated duringfeeding, such as in tapping operations that require movement of theladle. As shown in FIGS. 1 to 3, the chute may be pivoted at its upperend, as indicated at 44, to a bracket 45 mounted on the frame 5.

Midway of its length the chute 43 is provided with wheels 46 which rollupon the arcuate plate 47 supported from the stationary frame 5. Thechute 43 may be constructed with a replaceable section 48 at thedischarge end exposed close to the molten metal in the ladle.

Mechanical means may be provided for retracting the chute 43 to initialposition when not in operation. Such means is shown as a counter-balancedevice comprising a cable or equivalent flexible member 49 attached toedge of the chute toward the feeder conveyor, and located over a pulley50, with a counter-weight 51 attached to the other end of the cable.

The ladle indicated at 52 is shown mounted upon a car 53 by means ofwhich it may be moved relative to the feeder conveyor during tappingoperations that require movement of the ladle.

Means is provided for rotating the chute 43 upon its pivot as the ladleis moved so as to always direct the ladle additions into the ladle atthe desired point for maximum alloying results.

This means includes a mast 54, pivotally mounted as at 55, upon one sideof the ladle car 53. The counterweight 56 at the lower end of the masturges the mast into vertical position resting against the adjacent ladletrunnion 57, as shown in FIGS. 1 and 2. The offset upper end 58 of themast 54 is adjusted to contact the horizontal portion 59 of the chutepivot bar 60.

As the ladle car is moved toward the right, as viewed in FIG. 1, theupper offset end 58 of the mast in contact with the horizontal portion59 of the chute pivot bar, will rotate the chute 43 upon its pivot so asto continue to direct the chute toward the center of the ladle.

Referring back to the automatic weighing means, each of the hoppers 1and 2 may be supported by either three or four of the electric loadcells 10. When four load cells are used, one load cell supports eachcorner of a hopper.

As illustrated in FIGS. 1 to 3 of the drawings, two load cells maysupport the two corners of one end of a hopper, and a third load cellmay be located intermediate the corners at the other end of the hopper.

In FIG. 9 is shown diagrammatically the control circuit for one of thehoppers. Power is supplied on the lines 61 and 62. A double pole switch63 is provided for connecting the lines 61 and 62 to the terminals 64and 65 respectively.

Wires 66 and 67 lead from the terminals 64 and 65 respectively to theelectronic scale 11. The pointer 68 on the scale dial registers theweight of material in the hopper. The adjustable pointer 69 is adjustedrelative to the pointer 68 by means of a knob 70 on the outside of thedial.

Conductor 71 leads from switch terminal 64 through normally openpush-button type starting switch 72, normally closed push-button typestop switch 73, normally closed micro-switch 74 to relay 75.

Conductor 76 leads from switch terminal 65 to other side of relay 75.Shunt circuit 77 is located around normally open starting switch 72 andnormally open relay switch 78 is located in shunt circuit 77 andoperated by relay 7 5.

A conductor leads from wire 71 through normally open relay switch 80 toterminal 81. A wire 82 leads from terminal 81 through indicating light83 to wire 76. Selector switch 84 is pivoted on terminal 81 and adaptedto selectively contact terminals 85 and 86.

A solenoid air valve 87 is located between the terminal 85 and theconductor 76 for controlling the air vibrator 9 on the correspondinghopper gate 7. In like manner an electric motor 88 for operating theelectric vibrator 8 is located between the terminal 86 and the conductor76.

The electric load cells or transducers supporting the 6 hopper areconnected to the electronic instrument scale 11 by conductor 89, totransmit measurement thereto.

To operate the apparatus, the operator first sets the adjustable pointer69 on each scale dial for the weight of material required from thathopper. The operator then sets the selector switch 84 for choice ofpower for gate operation, either the air-powered vibrator 9 through theair solenoid valve 87, or the electric vibrator 8 through the motor 88.The two independently-powered vibrators provide for an emergencyswitch-over in case one or the other fails.

The operator then pushes the starting button 72 to energize the relay75, and close the circuit to start the gate vibrator as selected by theselector switch 84, and discharge material from the storage hopper.

As the material is discharged from the hoppers, the scale dial pointersmove back toward 0. The microswitch 74, or mercury switch which isattached to the shaft of the scale dial adjustable pointer, opens whenthis pointer returns to 0.

An adjustable mechanism may be set to trip slightly ahead of 0 to allowfor gate cut-off dribble, the gate control circuit opens and stops thegate vibrator.

In case of electric power failure affecting both gate vibrators (air andelectric) the gate maybe operated from the control console by air valveto operate air-powered gate vibrator through by-passing air line. Ifscale dial is still operating manual gate operation guided by watchingthe weight selection pointer as it returns to 0 will still assureaccurate weight withdrawal from the storage hoppers.

The gate operation may be stopped for emergency or other reason bypushing the stop button 73, de-energizing the relay 75 which opens thecircuit.

The required amount of additions from the storage hoppers 1 and 2 may bemetered into the feeder conveyor 13 before said feeder conveyor isoperated, or, if the automatic weighing mechanism is functioningproperly, the feeder conveyor may be operated simultaneously with theoperation of the weighing mechanism, or the feeder conveyor may bestarted at any time during the operation of the weighing mechanism,since the operation of each is independent of the other,

The load cells 10 may have a ball mounting as indicated at 90 in FIG. 6,but it should be understood that this feature is disclosed in a pendingapplication owned by The Atlas Car & Manufacturing Company, and no claimis made to the same by applicant.

In FIGS. 6 to 8 are shown shields for protecting the electric load cellsfrom heat and impact typically found 1n steel mill operation.

These shields are in the form of a metal box lined with high temperatureinsulation, hinged for easy access to the cell for servicing. The typeof shield shown in FIGS. 6 and 7 is best adapted for protecting loadcells located intermediate the corners of a hopper or the like. Theshield is formed of a stationary section 91 and a hinged section 92.

The stationary section comprises a back wall 93 and integralsubstantially triangular side wall portions 94 extending forwardly fromthe upper portion of each side edge thereof. The hinged sectioncomprises the front wall 95 hinged at its lower end to the base plateupon which the load cell 10 is supported, as at 96, and the side walls97 having the arcuate upper edges 98 shaped to fit the correspondingedges of the stationary side walls 94.

Each section is formed of a metal shell, which may be a bright-surfacedheat-reflective metal, enclosing a high temperature insulation 99. Ametal flange 100 on the stationary section overlaps the joint betweenthe two sections.

In FIG. 8 is shown a form of shield best adapted for protecting loadcells at the corners of a hopper or the like. This shield comprises thestationary section 101 in the form of an upright angle member.

This section may comprise the metal shell 102 with high temperatureinsulation material 103 therein. The hinged section 104 may be in theform of a heavy steel angle member hinged at one vertical edge to thecorresponding vertical edge of the stationary section as shown at 105,and having a lip 106 at its swinging edge to engage over thecorresponding edge of the stationary section.

Although vibratory gates are shown for the hoppers in FIGS. 1 to 3, thisis only by way of example and various conventional types of gates suchas knife blade, clam shell, rotary bucket and others may be substitutedfor the vibrating gates illustrated.

By way of example only, a rotary bucket gate is shown in FIG. 10. Thelower tapered portion of a hopper is shown at 3a, with outlet 4a. Thegate indicated generally at 108 has the segmental flanges 109 at itssides, pivoted at 110 to the lower portion of the hopper.

The gate 108 may be opened by the air cylinder 111 pivotally mounted atits upper end to the hopper, as at 112, the piston rod 113 beingpivotally connected at 114 to the gate.

A gear segment 115 on one side of the gate meshes with the pinion 116,journalled upon a bracket 117 on the hopper. An electric motor ofreversing type may be connected to the shaft 118 of the pinion 116, asan alternate drive means.

In event of failure of both electric and pneumatic power, a hand crank119 is attached to the shaft 118 for manually operating the gate 108.

From the above it will be obvious that the ladle additions feederdisclosed is very flexible in operation and use. The shaker pan of thefeeder conveyor may be operated throughout the operation of theautomatic weighing mech anisrn, or started at any time during theoperation thereof, or may remain stationary until the required amount ofadditions materials has been placed thereon, at the option of theoperator.

All of the controls may be remotely located, housed in a single cabinetor the like, including the scale dials, indicator lights, gate operationcontrols, selector switch (when alternate gate operation means isincorporated), feeder conveyor controls (including rate of feed andalternate drive means when incorporated) and by-pass manual controlmeans for weighing and conveying.

The electric load cells supporting the hoppers have mounting meansproviding protection for the load cells from heat and impact, and havehinged parts for easy access to the load cells for servicing.

The pivoted gravity chute onto which the feeder conveyor discharges,directs the ladle additions into the ladle at the desired point formaximum alloying results, and is arranged to be automatically rotated bymovement of the ladle, to maintain the desired position during tappingoperations that require movement of the ladle.

The feeder may be constructed as a unit with the storage hoppers Withinthe same structural frame as the conveyor, or with the hoppers andconveyor separately supported, either upon the frame base or suspendedfrom hangers attached overhead. The contour of design is fully flexibleand adaptable to any platform or furnace arrangement within broadlimits.

In the foregoing description certain terms have been used for brevity,clearness and understanding, but no unnecessary limitations are to beimplied therefrom beyond the requirements of the prior art, because suchwords are used for descriptive purposes herein and are intended to bebroadly construed.

Moreover, the embodiments of the improved construction illustrated anddescribed herein are by way of example, and the scope of the presentinvention is not limited to the exact details of construction.

Having now describe-d the invention or discovery, the construction, theoperation, and use of preferred embodiments thereof, and theadvantageous new and useful results obtained thereby; the new and usefulconstruction,

and reasonable mechanical equivalents thereof obvious to those skilledin the art, are set forth in the appended claims.

I claim:

1. Ladle addition feeding mechanism including material hoppers, meansfor discharging predetermined amounts of materials from said hoppers, afeeder conveyor positioned beneath said hoppers for receiving materialsdischarged from the hoppers, said feeder conveyor comprising stationaryside walls and a horizontal longitudinally reciprocal shaker pan andmeans for reciprocating said shaker pan independently of the hopperdischarge means to discharge material at a controlled rate from thefeeder conveyor into a ladle, whereby feeding of the required amount ofmaterials from said hoppers into said feeder may be started at any timeprior to topping of a heat of metal into the ladle and reciprocation ofsaid shaker pan may be started at any time during said topping.

2. In ladle addition feeding mechanism including a material hopperhaving a discharge outlet, gate means normally closing said outlet,electric load-measuring means, an electric circuit in which saidload-measuring means is located, and gate-operating means controlled bysaid electric circuit whereby a predetermined amount of material may bedischarged through said outlet, the improvement characterized by asubstantially horizontal conveyor positioned beneath said gate forreceiving material discharge-d from said hopper, said conveyorcomprising a longitudinally reciprocal shaker pan and stationary sidewalls and independent means for reciprocating said shaker pan, wherebyfeeding of the required amount of material from the material hopper intosaid horizontal conveyor may be started at any time prior to tapping ofa heat of metal into the ladle, and reciprocation of said shaker pan maybe started at any time during said tapping to feed said material fromsaid conveyor into the ladle.

3. In ladle addition feeding mechanism including a material hopperhaving a discharge outlet, gate means normally closing said outlet,electric load-measuring means, an electric circuit in which saidload-measuring means is located, and gate-operating means controlled bysaid electric circuit whereby a predetermined amount of material may bedischarged through said outlet, the improvement characterized by asubstantially horizontal conveyor positioned beneath said gate forreceiving material discharged from said hopper, said conveyor comprisinga longitudinally reciprocal shaker pan and downwardly convergingstationary side walls and independent means for reciprocating saidshaker pan, whereby feeding of the required amount of material from thematerial hopper into said horizontal conveyor may be started at any timeprior to tapping of a heat of metal into the ladle, and reciprocation ofsaid shaker pan may be started at any time during said tapping to feedsaid material from said conveyor into the ladle.

4. In ladle addition feeding mechanism including a material hopperhaving a discharge outlet, gate means normally closing said outlet,electric load-measuring means, an electric circuit in which saidload-measuring means is located, and gate-operating means controlled bysaid electric circuit whereby a predetermined amount of material may bedischarged through said outlet, the improvement characterized by asubstantially horizontal conveyor positioned beneath said gate forreceiving material discharged from said hopper, said conveyor comprisinga longitudinally reciprocal shaker pan having upturned flanges at itslongitudinal edges and stationary side walls of considerably greaterheight than the upturned flanges of said shaker pan and independentmeans for reciprocating said shaker pan, whereby feeding of the requiredamount of material from the material hopper into said horizontalconveyor may be started at any time prior to tapping of a heat of metalinto the ladle, and reciprocation of said shaker pan may be started atany time during said tapping to feed said material from said conveyorinto the ladle.

5. In ladle addition feeding mechanism including a material hopperhaving a discharge outlet, gate means normally closing said outlet,electric load-measuring means, an electric circuit in which saidload-measuring means is located, and gate-operating means controlled bysaid electric circuit whereby a predetermined amount of material may bedischarged through said outlet, the improvement characterized by asubstantially horizontal conveyor positioned beneath said gate forreceiving material discharged from said hopper, said conveyor comprisinga longitudinally reciprocal shaker pan having upturned flanges at itslongitudinal edges and downwardly converging stationary side walls ofconsiderably greater height than the upturned flanges of said shaker panand independent means for reciprocating said shaker pan, whereby feedingof the required amount of material from the material hopper into saidhorizontal conveyor may be started at any time prior to tapping of aheat of metal into the ladle, and reciprocation of said shaker pan maybe started at any time during said tapping to feed said material fromsaid conveyor into the ladle.

6. In ladle additional feeding mechanism including a material hopperhaving a discharge outlet, gate means normally closing said outlet,electric load-measuring means, an electric circuit in which saidload-measuring means is located, and gate-operating means controlled bysaid electric circuit whereby a predetermined amount of material may bedischarged through said outlet, the improvement characterized by asubstantially horizontal conveyor positioned beneath said gate forreceiving material discharged from said hopper, said conveyor comprisinga longitudinally reciprocal shaker pan and stationary side walls, saidconveyor having a capacity for the maximum requirement of additionmaterial for one heat, and independent means for reciprocating saidshaker pan, whereby feeding of the required amount of material from thematerial hopper into said horizontal conveyor may be started at any timeprior to tapping of a heat of metal into the ladle, and reciprocation ofsaid shaker pan may be started at any time during said tapping to feedsaid material from said conveyor into the ladle.

7. Ladle addition feeding mechanism including a material hopper, meansfor discharging a predetermined amount of material from said hopper, ahorizontal feeder conveyor positioned beneath said hopper for receivingmaterial discharged therefrom, said feeder conveyor comprisingstationary side walls and a horizontal longitudinally reciprocal shakerpan, a vibratory drive unit connected to the shaker pan, electric motormeans, fluid motor means, chain and sprocket gearing with over-ride typeclutches connecting said motor means to said vibratory drive unit, andvalve controlled means for admitting fluid pressure to the fluid motormeans to discharge material at a controlled rate from the feederconveyor into a ladle, whereby in the event of failure of power toeither of said motor means the other motor means may operate saidvibratory drive unit.

8. Ladle addition feeding mechanism including a material hopper having adischarge outlet, gate means normally closing said outlet, electricpower-operated means connected to said gate means, fluid power-operatedmeans connected to said gate means, valve controlled means for admittingfluid pressure to said fluid power-operated means for operating saidgate for discharging a predetermined amount of material through saidoutlet, a substantially horizontal conveyor positioned beneath said gatefor receiving material discharged from said hopper, and independentmeans for operating said conveyor for discharging material therefromwhereby feeding of the required amount of material from the hopper intosaid horizontal conveyor may be started at any time prior to tapping ofa heat of metal into the ladle, and operation of said conveyor may bestarted at any time during said tapping to feed said material from saidconveyor into the ladle.

9. 1n ladle addition feeding mechanism including a material hopperhaving a discharge outlet, gate means normally closing said outlet,electric load-measuring means, an electric circuit in which saidload-measuring means is located, and gate-operating means controlled bysaid electric circuit whereby a predetermined amount of material may bedischarged through said outlet, the improvement characterized by asubstantially horizontal conveyor positioned beneath said gate forreceiving material discharged from said hopper, said conveyor comprisinga longitudinally reciprocal shaker pan and stationary side walls andindependent means for reciprocating said shaker pan, for moving theshaker pan forward relatively slowly and backward relatively rapidly,whereby feeding of the required amount of material from the materialhopper into said horizontal conveyor may be started at any time prior totapping of a heat of metal into the ladle, and reciprocation of saidshaker pan may be started at any time during said tapping to feed saidmaterial from said conveyor into the ladle.

10. In ladle addition feeding mechanism as defined in claim 2, in whichthe discharge outlet is located at the lower end of a downwardly andinwardly inclined side Wall of the hopper, and the gate means for saidoutlet is a rotary bucket gate comprising segmental flanges pivoted attheir inner ends upon the lower portion of the hopper and an outer wallconnected to the outer edges of said segments, the lower end of saidouter wall of the gate being normally located at the bottom of saiddischarge outlet and the upper edge thereof being normally located nearthe discharge outlet, and means for oscillating said rotary bucket gatedownwardly to open and upwardly to close the discharge outlet.

References Cited by the Examiner UNITED STATES PATENTS 1,040,703 10/1912Leftwich 21442 1,493,118 5/1924 Loughram 22107 1,521,276 12/1924 Cave etal. 19323 2,473,160 6/1949 Madrigal 22112 2,665,798 1/1954 Hagenbook198220 2,679,335 5/1954 Bell 2281 2,823,791 2/1958 Barrett et al 1982242,917,207 12/1959 Prowse et al. 198-39 X 2,932,430 4/1960 Dennis 222553,010,563 11/1961 Keegan 198-220 3,024,765 3/1962 Reed 198224 3,058,62110/1962 Stenzel 198-39 FOREIGN PATENTS 183,260 7/ 1922 Great Britain.

J. SPENCER OVERHOLSER, Primary Examiner.

MARCUS U. LYONS, MICHAEL V. BRINDISI,

Examiners.

8. LADE ADDITION FEEDING MECHANISM INCLUDING A MATERIAL HOPPER HAVING ADISCHARGE OUTLET, GATE MEANS NORMALLY CLOSING SAID OUTLET, ELECTRICPOWER-OPERATED MEANS CONNECTED TO SAID GATE MEANS, FLUID POWER-OPERATEDMEANS CONNECTED TO SAID GATE MEANS, VALVE CONTROLLED MEANS FOR ADMITTINGFLUID PRESSURE TO SAID FLUID POWER-OPERATED MEANS FOR OPERATING SAIDGATE FOR DISCHARGING A PREDETERMINED AMOUNT OF MATERIAL THROUGH SAIDOUTLET, A SUBSTANTIALLY HORIZONTAL CONVEYOR POSITIONED BENEATH SAID GATEFOR RECEIVING MATERIAL DISCHARGED FROM SAID HOPPER, AND INDEPENDENTMEANS FOR OPERATING SAID CONVEYOR FOR DISCHARGING MATERIAL THEREFROMWHEREBY FEEDING OF THE REQUIRED AMOUNT OF MATERIAL FROM THE HOPPER INTOSAID HORIZONTAL CONVEYOR MAY BE STARTED AT ANY TIME PRIOR TO